ROLE OF INTRACRANIAL-PRESSURE MONITORING IN SEVERELY HEAD-INJURED PATIENTS WITHOUT SIGNS OF INTRACRANIAL HYPERTENSION ON INITIAL COMPUTERIZED-TOMOGRAPHY

Previous studies have suggested that only a small proportion (< 15%) o f comatose head-injured patients whose initial computerized tomography (CT) scan was normal or did not show a mass lesion, midline shift, or abnormal basal cisterns develop intracranial hypertension. The aim of the present study was to re-examine this finding against a background of more intensive monitoring and data acquisition. Eight severely hea d-injured patients with a Glasgow Coma Scale score of 8 or less, whose admission CT scan did not show a mass lesion, midline shift, or effac ed basal cisterns, underwent minute-to-minute recordings of arterial b lood pressure, intracranial pressure (ICP), and cerebral perfusion pre ssure (CPP) derived from blood pressure minus ICP. Intracranial hypert ension (ICP greater than or equal to 20 mm Hg lasting longer than 5 mi nutes) was recorded in seven of the eight patients; in five cases the rise was pronounced in terms of both magnitude (ICP greater than or eq ual to 30 mm Hg) and duration. Reduced CPP (less than or equal to 60 m m Hg lasting longer than 5 minutes) was recorded in five patients. Sev erely head-injured (comatose) patients whose initial CT scan is normal or does not show a mass lesion, midline shift, or abnormal cisterns n evertheless remain at substantial risk of developing significant secon dary cerebral insults due to elevated ICP and reduced CPP. The authors recommend continuous ICP and blood pressure monitoring with derivatio n of CPP in all comatose head-injured patients.